atomic.h : Add atomic64 cmpxchg, xchg and add_unless to alpha
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
--- a/include/asm-alpha/atomic.h
+++ b/include/asm-alpha/atomic.h
@@ -175,19 +175,62 @@ static __inline__ long atomic64_sub_return(long i, atomic64_t * v)
return result;
}
-#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
+#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
+
+#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+/**
+ * atomic_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
#define atomic_add_unless(v, a, u) \
({ \
- int c, old; \
+ __typeof__((v)->counter) c, old; \
c = atomic_read(v); \
- while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
+ for (;;) { \
+ if (unlikely(c == (u))) \
+ break; \
+ old = atomic_cmpxchg((v), c, c + (a)); \
+ if (likely(old == c)) \
+ break; \
c = old; \
+ } \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+/**
+ * atomic64_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic64_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#define atomic64_add_unless(v, a, u) \
+({ \
+ __typeof__((v)->counter) c, old; \
+ c = atomic64_read(v); \
+ for (;;) { \
+ if (unlikely(c == (u))) \
+ break; \
+ old = atomic64_cmpxchg((v), c, c + (a)); \
+ if (likely(old == c)) \
+ break; \
+ c = old; \
+ } \
+ c != (u); \
+})
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
-
